// CodeMirror, copyright (c) by Marijn Haverbeke and others
// Distributed under an MIT license: http://codemirror.net/LICENSE

(function(mod) {
  if (typeof exports == 'object' && typeof module == 'object')
    // CommonJS
    mod(require('../../lib/codemirror'));
  else if (typeof define == 'function' && define.amd)
    // AMD
    define(['../../lib/codemirror'], mod);
  // Plain browser env
  else mod(CodeMirror);
})(function(CodeMirror) {
  'use strict';

  CodeMirror.defineMode('pascal', function() {
    function words(str) {
      var obj = {},
        words = str.split(' ');
      for (var i = 0; i < words.length; ++i) obj[words[i]] = true;
      return obj;
    }
    var keywords = words(
      'and array begin case const div do downto else end file for forward integer ' +
        'boolean char function goto if in label mod nil not of or packed procedure ' +
        'program record repeat set string then to type until var while with',
    );
    var atoms = { null: true };

    var isOperatorChar = /[+\-*&%=<>!?|\/]/;

    function tokenBase(stream, state) {
      var ch = stream.next();
      if (ch == '#' && state.startOfLine) {
        stream.skipToEnd();
        return 'meta';
      }
      if (ch == '"' || ch == "'") {
        state.tokenize = tokenString(ch);
        return state.tokenize(stream, state);
      }
      if (ch == '(' && stream.eat('*')) {
        state.tokenize = tokenComment;
        return tokenComment(stream, state);
      }
      if (/[\[\]{}\(\),;\:\.]/.test(ch)) {
        return null;
      }
      if (/\d/.test(ch)) {
        stream.eatWhile(/[\w\.]/);
        return 'number';
      }
      if (ch == '/') {
        if (stream.eat('/')) {
          stream.skipToEnd();
          return 'comment';
        }
      }
      if (isOperatorChar.test(ch)) {
        stream.eatWhile(isOperatorChar);
        return 'operator';
      }
      stream.eatWhile(/[\w\$_]/);
      var cur = stream.current();
      if (keywords.propertyIsEnumerable(cur)) return 'keyword';
      if (atoms.propertyIsEnumerable(cur)) return 'atom';
      return 'variable';
    }

    function tokenString(quote) {
      return function(stream, state) {
        var escaped = false,
          next,
          end = false;
        while ((next = stream.next()) != null) {
          if (next == quote && !escaped) {
            end = true;
            break;
          }
          escaped = !escaped && next == '\\';
        }
        if (end || !escaped) state.tokenize = null;
        return 'string';
      };
    }

    function tokenComment(stream, state) {
      var maybeEnd = false,
        ch;
      while ((ch = stream.next())) {
        if (ch == ')' && maybeEnd) {
          state.tokenize = null;
          break;
        }
        maybeEnd = ch == '*';
      }
      return 'comment';
    }

    // Interface

    return {
      startState: function() {
        return { tokenize: null };
      },

      token: function(stream, state) {
        if (stream.eatSpace()) return null;
        var style = (state.tokenize || tokenBase)(stream, state);
        if (style == 'comment' || style == 'meta') return style;
        return style;
      },

      electricChars: '{}',
    };
  });

  CodeMirror.defineMIME('text/x-pascal', 'pascal');
});
